化学沉淀-溶剂沉淀法脱除湿法磷酸中氟的研究

Defluorination of wet-process phosphoric acid with chemical precipitation-solvent precipitation

以乙醇为溶剂,RNH2为沉淀剂,采用化学沉淀-溶剂沉淀法对湿法磷酸进行净化,在乙醇与预处理酸体积比为2.0、溶剂沉淀剂用量为3.5%、反应温度40℃、反应时间100min条件下,脱氟率可达到96%以上,磷收率为86%以上.

The purification of wet - process phosphoric acid was researched with chemical precipitation - solvent precipitation with ethanol as solvent and RNH2 as precipitator. The optimized process parameters were obtained：the volume ratio of ethanol to pretreatment acid 2： 1, solvent precipitator 3.5 % （w）, reaction temperature 40℃ ,reaction time 100 rain. Under the condition, the ratio of defluorination was up to 96% and the yield of phosphorus was up to 86%.